The scrapie prion protein (PrPsc) is the major component of the infectious particle (prion) responsible for a group of fatal neurodegenerative disorders, including Creutzfeldt-Jakob disease and kuru in human beings, and scrapie in animals. During prion infection, PrPsc is generated by posttranslational modification of a glycolipid-anchored membrane protein of the host called PrPc. While PrPsc has been the subject of intensive study, much less attention has been paid to PrPc, whose physiological function is unknown. The purpose of the present application is to explore several interrelated questions concerning the cellular properties of PrPc, with a view to understanding the normal function of this isoform, as well as to establishing possible therapeutic strategies for inhibiting its conversion to PrPsc.